I received an email with one UCI (sponsor's UCI), I entered/selected all info as below,No, online application too can be linked to the gckey account. Sponsor can link the application to the sponsor's account using the sponsor UCI, PA's details and entering the number of people in the application as 2.
PERMANENT RESIDENCE --- FAMILY SPONSOR (SPOUSE) --- ENTER UCI AND APPLICATION NUMBER --- PA's BIRTH PLACE AND COUNTRY --- NUM OF APPLICANTS = 2
But still not working, I also tried entering passport info (PA's) instead of birth place and country, still no luck and I exeeded given num of times to eneter info, so I have to await 24 hours to re-try everything